standard and customized electric heat exchangers - renewable energies

Thanks to its experience in the energy sector, Reart has become an Enel partner for the supply of 17 geothermal plants for Enel plants in Tuscany.

General characteristics of electric exchangers.

The electric exchangers produced by Reart are the optimal solution for systems where it is necessary to heat the process fluid passing through the electric exchanger.

The fluid enters, through the flanged or threaded connection on the tank, and exits from the outlet nozzle of the exchanger at the desired temperature.

The heater inserted inside the tube/tank (specially sized according to the project data), is able to raise the temperature of the outgoing fluid to the condition required by the customer or by the project specifications.

Thanks to the experience of the technical office, the electric exchangers can be designed and manufactured for the following types of fluids:

  • Thermal oil and fuels
  • Hydrocarbons
  • Industrial, fresh and demineralised water
  • Sea water
  • Natural gas, technical and process gases
  • Air or Nitrogen
  • Vapour
  • Salt
  • hydrogen

The electrical power installed on the electric exchangers can vary up to thousands of kW according to specific customer requests.

The electric exchanger consists of an electric heating bundle with several resistive elements connected to each other and welded on a tank coupling flange and inserted inside a tube (exchanger shell) sized and designed according to the project data (temperature and pressure ) and in compliance with regulations according to the country of destination: VSR, PED, ASME, U-STAMP, TEMA, ADMERKBLATTER, STOOMWEZEN.

The tank and the heater are sized (Materials and dimensions) by the technical office based on the operating conditions indicated in the customer’s reference specifications and on the design conditions by means of thermodynamic and mechanical calculation software.

Different materials are applied to the part under pressure (tank and coupling flanges) and to the heater depending on the operating conditions:

  • Carbon and/or low alloy steel for low temperature conditions and non corrosive fluids.
  • Stainless steel for aggressive fluids and high temperatures (Aisi 304 – 316L).
  • Titanium for marine and offshore applications.

For the heating elements (electric heating beam) the following can be used:

  • Austenitic materials such as AISI 321 for corrosive fluids and high temperatures.
  • Austenitic materials such as AISI 316L for corrosive fluids and low temperatures.
  • Noble alloys such as incoloy 800 for high temperature systems.
  • Titanium for marine and offshore installations for salt water use.

Depending on the maximum operating temperature of the system, the electrical enclosure of the heater connections can be in direct contact with the heater flange or in the “cold head” execution. The protection rating can be IP55, IP65 or IP66 with relative sealing gasket. The manufacture materials can be in carbon steel painted with zinc aluminum paint or otherwise in Aisi 304 or Aisi 316L stainless steel.

The electric exchangers are sized by the technical office, with the aid of software for thermodynamic sizing, thanks to which it is possible to obtain the real operating conditions, based on the needs and specifications of the customer to create flows at a controlled temperature.

Thanks to the use of this software for the sizing of the electric exchangers, it is possible to define the main parameters including:

  • Electric power needed
  • Process side pressure drops
  • Surface load or specific power
  • Maximum surface temperature of the heating element
  • Fluid flow rate inside the tank
  • Dimensions of the electric exchanger
  • Building materials
  • Conditions of the exchanger during normal expected operating conditions.

The exchanger can be supplied together with the relative insulation supports, the exchanger lifting eyebolts, the tank support saddles for mechanical fixing of the exchanger, the process control instrumentation (sensors thermals), and any connections to the tank (venting and drain).

Reart manufactures process skids and supplies the turnkey package by supplying, in addition to the electric exchanger, the relative electrical command and control panel of the exchanger.  

 The electric exchangers can be equipped with the following accessories:

  1. 4-20mA temperature transmitters
  2. Process control and safety sensors and heater (thermostats, PT100 temperature probes, thermocouples).
  3. Power and safety cable glands.
  4. Electric control panel and heater control.
  5. Anti-condensation heater (prevention against humidity).

The experience Reart in many years of presence on the market in various sectors, allows to give its customers the most suitable technical solutions for the type of application required.

Reart is able to provide the following services to support the products supplied:

  • Commissioning & start-up assistance at the customer’s premises
  • Commissioning at the customer
  • Maintenance assistance of existing plants supplied.
  • Spare parts on supplied products.

For electric exchangers, the following documentation is provided in the final certification file accompanying the product:

  • Declaration of conformity
  • Use and maintenance manual
  • Exchanger assembly drawings
  • Technical data sheets of the components used and relative declarations of conformity of the suppliers
  • Final testing Reart.

Customized solutions are also provided on request and on customer specifications.

For more details refer to the section Standard and Customized Electric Exchangers (Process Gases and Fluids) or otherwise contact Reart.